I discovered DMT a few months ago and was blown away. I had a few small breakthroughs but nothing McKennaesque. I thought dosage was the issue and kept upping the dose... instead of breaking through I would go in this strange trance and my friends would appear around me and talk to me, one of them was telling how to hold the lighter properly. Every chain of thoughts was a separate instance of myself talking to me. It reminded me Susan Blackmore's meme machine and being a bit cynical I imagined we were just vessel for memes, thoughts and other demons and that we didn't really exists...
Another feeling I've had taking DMT is one of wholeness... saying we are the universe, the whole universe. Looking at itself.